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61.
最佳传力特性的偏置曲柄滑块机构解析法设计 总被引:1,自引:0,他引:1
本文根据偏置曲柄滑块机构的运动特性和传力特性所建立的函数关系,运用极值理论推导出给定条件下传力特性最佳的计算公式,大大方便了设计应用,值得推广。 相似文献
62.
Zong He 《中国航天(英文版)》2010,(2)
<正>On April 24,1970,China successfully launched its first man-made satellite,DFH-1. It was a milestone in China's space history,making China the 5th country capable of independently developing, launching and operating satellites following the former Soviet Union, the United States,France and Japan. Since then China's satellites have been launched into space one after another and benefit mankind due to their advantages. Over the past 40 years,China has 相似文献
63.
He Ying 《中国航天(英文版)》2012,(1):8
China on February 6,2012 released a high-resolution full map of the entire moon,marking the best view yet of the lunar surface captured by China’s second moon orbiter,Chang’e 2.While other countries have acquired better images of certain portions of 相似文献
64.
65.
It is urgent to carry out detailed research on storage performance of rubber sealing ring to get the criterion for its storage life. This paper acquires material ageing regularity by theoretical analysis and experimental confirmation. On this condition, failure mode and failure criterion of typical sealing structure is studied, and the failure mechanism is found. Thus by analyzing the stress distribution, the relationship between ageing state and sealing condition is established. Rationalization proposal is put forward and storage life of sealing ring is evaluated. The research mentionedabove has special reference to the design of sealing structures and can provide reference for prolonging their service life. 相似文献
66.
67.
何皇冕 《民用飞机设计与研究》2014,(3):85-87
应急照明系统用于为机上人员的应急撤离提供照明,当飞机电源失效后自动开启。因此,应急照明的触发时机及方式将直接影响机上人员应急撤离的效率。目前,民用飞机一般都用应急照明电源充电线路的掉电来触发应急照明,该触发方式限制了应急照明的开启时间,对适航取证存在风险。提出了一种全新的应急照明触发电路设计方法,并详细介绍了其设计原理和控制逻辑。该应急照明触发电路设计可显著降低适航取证的风险和飞机的研发成本,为民用飞机应急照明系统的设计提供重要的指导意义。 相似文献
68.
Liming He Lixin Wu Sergey Pulinets Shanjun Liu Fan Yang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
A precise determination of ionospheric total electron content (TEC) anomaly variations that are likely associated with large earthquakes as observed by global positioning system (GPS) requires the elimination of the ionospheric effect from irregular solar electromagnetic radiation. In particular, revealing the seismo-ionospheric anomalies when earthquakes occurred during periods of high solar activity is of utmost importance. To overcome this constraint, a multiresolution time series processing technique based on wavelet transform applicable to global ionosphere map (GIM) TEC data was used to remove the nonlinear effect from solar radiation for the earthquake that struck Tohoku, Japan, on 11 March, 2011. As a result, it was found that the extracted TEC have a good correlation with the measured solar extreme ultraviolet flux in 26–34 nm (EUV26–34) and the 10.7 cm solar radio flux (F10.7). After removing the influence of solar radiation origin in GIM TEC, the analysis results show that the TEC around the forthcoming epicenter and its conjugate were significantly enhanced in the afternoon period of 8 March 2011, 3 days before the earthquake. The spatial distributions of the TEC anomalous and extreme enhancements indicate that the earthquake preparation process had brought with a TEC anomaly area of size approximately 1650 and 5700 km in the latitudinal and longitudinal directions, respectively. 相似文献
69.
沈阳机床以紧密联合具有传统学科优势的高校院所为基础、以主动贴近用户深入了解用户工艺需求为途径、以积极承担国家各级政府重大科技项目为载体,着重开展面向航空领域的研究与工作。 相似文献
70.
He Ying 《中国航天(英文版)》2011,(2)
(Continued)THE 62ND LAUNCH On September 1,2000, a LM-4B launch vehicle lifted off with ZY-2 (01 resources satellite from Taiyuan Satellite Launch 相似文献